/Engine/Source/Runtime/GeometryCore/Public/DynamicMesh/MeshTangents.h
Initialize Tangents from theFDynamicMeshAttributeSetof SourceMesh
false if tangent attributes do not exist
bool CopyTriVertexTangents ( const [FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) & SourceMesh )